Study on the synthesis and theoretical calculation of a chlorine‐substituted thiosemicarbazone derivative

In this paper, the compound (E)‐N‐(3,5‐dimethylphenyl)‐2‐(3‐chlorobenzylidene)thiosemicarb‐azone was synthesized and characterized by elemental analysis, Fourier transform infrared (FT‐IR), 1H nuclear magnetic resonance (NMR), 13C NMR. The crystal structure was determined by single‐crystal X‐ray diffraction tool, indicating that the compound belongs to the orthorhombic crystal system of the Fdd2 space group, where a = 14.0472(12) Å, b = 57.148(4) Å, c = 7.9633(6) Å, the chemical formula is C16H16ClN3S, Mr = 317.83, V = 6392.7(9) Å3, Z = 16, Dc = 1.321 Mg/m3, F(000) = 2656, R = 0.0339, wR = 0.0903. Analysis of crystal data shows that the molecular conformation has good planarity. Hirshfeld surface and two‐dimensional (2D) fingerprints were used to analyze the intermolecular hydrogen bonds. In addition, a more comprehensive theoretical calculation studies were carried out on synthetic compound, such as potential energy surface (PES) scan, reduced density gradient (RDG), and independent gradient model (IGM) analysis, atoms in molecules (AIM) analysis, highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) and UV‐visible spectra analysis. The combination of experimental and theoretical data proved that non‐covalent bonds play a vital role in maintaining the stability of molecule. Finally, molecular docking was used to research the interaction between the synthetic compound and the receptor protein (4C2L). Meanwhile, the results obtained by in vitro antifungal assay indicated that the synthetic compound possesses the most remarkable inhibitory effect for Fusarium graminearum. A new type of thiosemicarbazone was synthesized and characterized. There were experimental and theoretical researches on the conformational isomerism, intermolecular and intramolecular interactions, electronic properties, reaction sites and biological activity of synthetic compound. ​